(Adapted from the Abstract): The Department of Health and Human Services (DHHS) health objectives for the Year 2000 call for a decrease in the number of early adolescents who engage in sexual intercourse, and increase in condom use among sexually-active adolescents, and an increase in the provision by the primary care provider of age appropriate counseling for the prevention of STD's, including infection with HIV. However, no primary care counseling model is available which as demonstrated effectiveness in delaying early adolescent sexual activity or reducing risky sexual behavior. Accordingly, the Principal Investigator in this project proposes to: (1) refine a model STD/HIV prevention program for physicians and early adolescents; (2) conduct a pilot evaluation to determine whether an STD/HIV prevention program for physicians increases patient-provider discussion about sexual risks and alters patient intentions and behaviors regarding sex; and (3) determine whether STD/HIV risk assessment and education administered through a radio device (a "Walkman") can enhance patient-provider discussion about sexual risks and safer patient intentions and behaviors regarding sex. The model program for physicians and early adolescents, called ASSESS (Awareness, Skills Enhancement, and Social Support), is hypothesized to increase STD/HIV prevention intentions and to delay or decrease the risk of sexual activity among early adolescents. Six adolescent medicine physician practices in Washington, D. C. have agreed to participate in this study. The research staff will recruit 10 patients (50% females) of each physician's practice, age 12 through 15 years, for study participation during the pre-intervention phase and 54 patients (50% females) of each physician's practice, aged 12 through 15 years, during the post-intervention phase. All study physicians and their staffs will receive STD/HIV prevention training between the pre- and post- intervention study phases. All study patients will be assigned randomly to one of three study groups: Group I will be a usual care comparison group: Group II will receive radio-administered risk assessment and education and educational materials after the physician visit; and Group III will receive radio-administered risk assessment and education and educational materials before the physician visit such that physicians can review risk assessment information during visits with their patients. The patient-reported physician-patient discussions about STD/HIV risks will be assessed in the patient exit interviews. The patients' sexual intentions and behaviors will be measured by a telephone interview 3 and 12 months after the index physician visit.